1. Field of the Invention
The present invention concerns a device and system for releasably securing a watchband to a watch casing, and in particular, to a watchband connector pin formed of a shape memory material, preferably a shape memory metal alloy. The connector pin is durable due to the one piece design, economical to produce, and easy to operate.
2. Description of the Related Art
Wrist watches with replaceable bands have been known for more than half a century. The wrist watch requires replacement or exchange of wristbands for numerous reasons, most often when the band becomes worn or damaged. Modern wristwatches utilize a variety of mechanisms for attaching the watchband, that portion which encircles the wrist of tile wearer, to the watch casing. Most prevalent is the spring pin. A spring pin generally comprises an elongate metal cylinder, a spring means enclosed within the cylinder, and slide pins projecting from the ends of the cylinder and adapted to being urged outward from said cylinder by said spring and into receptacles formed in the watch casing.
The term "watch casing", as used herein, refers to that portion of the wrist watch assembly which surrounds the face of the watch and which houses the mechanical movement of the watch. Traditionally, the watch casing is provided with a receiving means, located on opposing ends of the watch face, whereby the watchband may be attached to the case.
There are numerous watch designs for both the watch case and the watchband. The most traditional designs include a generally circular or rectangular watch case having two somewhat rectangular, elongated watchband straps, the watchband straps generally being attached to opposing sides of the watch case (usually adjacent to the numeral "12" and "6" respectively of the watch face). Each watchband strap is attached to the watch casing via a pair of strap support arms which are generally formed integrally with, and projecting from, the watch case. A pair of support arms project from each side of the watch casing and the arms of a pair are spaced a distance apart corresponding approximately to the width of the watchband strap at the point of attachment. Located on the inside surface of each paired support arm, (i.e., the side facing the mate) is a small aperture or indentation sized to receive one end of a spring-loaded pin. The two ends of the pin engage the two respective apertures, such that the pin is supported between the pair of support arms. The watchband strap is usually provided with a sleeve through which the pin can be inserted prior to installing the pin on the watch casing.
The pin is either inserted through the extended arms and held in place by screw means, or the pin is spring-biased between the extended arm members. In some embodiments, the pin may be journalled between the extended arm members. In instances where the pin is removable, the watchband is removed by either unscrewing the pin from between the arm members or by compressing the spring-biased pin to release it from between the arms. The pin, which is positioned within a sleeve formed in the watchband, may be removed from the sleeve and reinserted in another wristband for attachment of the new band to the casing.
Current watchband connecting means have an inherent problem in that it is rather tricky to remove the band from the watch. A specialized hand tool or instrument is generally required to remove the spring-loaded pin and thereby the watchband strap from the watch casing and to subsequently reattach the same or a replacement strap.
The current practice for removing the watchband and subsequently replacing the strap or band is rather tedious. For example, an individual desiring to replace or change a watch band must first fit a specially adapted tool into the space where the band abuts the watch case. While holding the watch assembly stationary in one hand, the individual must with the other hand assert sufficient pressure, in the correct direction, to release the spring pin holding the band in place. Then, once the spring pin is released, removed from the band to be replaced, and inserted into the new band, the process must be repeated in reverse. The individual must align one end of the spring pin in the "receiving aperture" while utilizing the specialized watch tool to depress the pin inward and aligning the second end of the pin into the opposing hole in the watch casing.
This approach presupposes several things. First, it presupposes that an individual may own or be willing to purchase the specialized tool necessary to release the hinge or spring pin. Second, it presupposes that the individual has sufficient hand strength and dexterity to hold the watch assembly stationary while exerting directional pressure with the opposing hand. In most, if not all, instances an individual wanting to replace or change the watchband on their watch will be required to frequent a jewelry or watch repair store thereby rendering a what should be a relatively simply and inexpensive procedure costly and time consuming.
There is thus a need for a device by means of which a watchband may be readily and rapidly replaced as desired for aesthetic consideration, to facilitate repairs to the watch, or when the band is damaged or worn.
There has also recently been an increase in worldwide watch manufacture and competitiveness, and watch prices have dropped drastically. Watches can be purchased for a few dollars. One significant cost in watch manufacturing is the pin which connects the band to the case. There is thus a need for a more economical means for securing a watch band to a watch casing than the conventional approach which requires the multi-component spring pin. In the manufacturing context, cost considerations and ease of assembly are crucial, and current methods of attaching watch band straps to the watch casing are costly, inefficient, and inconvenient due to the complexity of pin assemblies on the market.
Further, there has also been a trend to market to fashion conscious consumers as a package a single watch casing with a number of interchangeable watch bands. The provision of a number of watch bands of various colors and designs facilitates the initial sale to the consumer, since the consumer is likely to find at least one of the offered watch bands to be desirable. Also, it is known that children and adolescents often participate in fads and trends, including use of neon and other bright colors to accentuate their clothing, and will want to change a watch band to match their current outfit. There is thus a need for a device which is simple enough to allow even children, without undue adult supervision, to readily change-out the watchbands on their wrist watches.
Attempts have been made to provide a system or device which will facilitate the replacement of watchbands or watch straps. For instance, U.S. Pat. No. 5,416,953 (Wah-Sang Hui) teaches the use of a link or eye on the strap which may be interlinked with a link or eye on the wrist watch, one of the links including a spring loaded catch to allow interlinkage.
However, the link assembly used to attach the wrist strap is mechanically quite complex and has several drawbacks. The link includes a fixed cylinder, a piston moveable along the cylinder, a compression coil spring located within the cylinder and a handle for use in retracting the piston into the cylinder against the action of the spring so as to open the link. Further, use of the attachment means taught by Hui requires that the replacement straps be specially manufactured to join the disclosed link assembly. Finally, due to the exposed handles, the linkage means is readily visible (not flush) with the watch casing.
For the foregoing reasons, there is a need for an easy, inconspicuous and economical device to allow for replacement of a watchband for aesthetic purposes, to facilitate repairs, and replacement when the current watchband is damaged or worn.